Gun perforator



P- CHARRIN GUN PERFORATORY Nov. 22, 1949 Filed y 31, 1946 2Sheejzs-Sheet l MP 01 Lzq rr :1]. .=1-E

INVENTOR.

Paul Charrin P. CHARRIN GUN PERFORATOR Nov. 22; 1949 2 Sheets-Shet 2Filed May 51, 1946 INVENTOR. Paul Gharrin Patented Nov. 22, 1949 UNITEDSTATES PATENT OFFICE GUN PEBFOBATOR Paul Houston, Tex. Application May31, 1916, Serial No. 673,424

1 Claims. .(cl. 164-05) .This invention relates to a gun perforator.

An object of the invention is to provide a. tool of the characterdescribed specially designed for use in perforating well casing andwhich includes a body provided with a plurality of radial gun barrelsand associated firing chambers to receive explosive charges withprojectiles, or bullets, in the barrels to perforate the casing uponfiring of the respective charges together with novel means forselectively firing the charges.

It is another object of the present invention to in a gun perforator ofthe character dewhich may, if desired, be made sections, preferablyjoined together by threads, thus facilitating the construction of a gunperforator carrying a plurality of barrels and the associatedprojectiles and firing charges.

It is a. further object of the invention to provide a gun perforator ofthe character described having a channel therein to receive a slidingcontact member whereby the charges are selectively fired and of suchconstruction that the necessity for insulating the channel is dispensedwithr A further object of the invention is to provide a gun perforatorof such construction that the pressure within the tool itself will besubstantially equal to the outside pressure to minimize provide,scribed, a body up of a plurality of the entrance of the well liquidinto the interior mechanism of the perforator. 1

The elimination of insulating materials, in the construction of a gunperforator, is important for the reason that such insulating materialsare either fragile or are not capable of withstanding the changes ntemperature to which a gun perforator is subiected while used in a deepwell; and for the further reason that a perforating gun can be moreeasily and cheaply manufactured if the insulation is minimized.

With the above and other objects in view the invention has particularrelation to certain novel features of construction, operation andarrangement of parts, examples of which are given in this specificationand illustrated in the accompanying drawings, wherein:

Figure 1 is a side elevation of the gun perforator, partly in section,shown located in a well.

Figure 2 is a fragmentary, vertical, sectional view thereof.

Figure 3 is a cross-sectional view taken on the line 3-3 of Figure 2.

Figure 4 is an enlarged, fragmentary, sectional view of a form ofcartridge support employed.

gonal view of another embodiment of the inven- Figure 6 is afragmentary, vertical, sectional view illustrating a form of slidingcontact employed; and,

Figure 7 is a fragmentary, transverse, sectional view taken on the line1-1 of Figure 6.

Referring now more particularly to the drawings wherein like numerals ofreference design te the same parts in each of the figures, the numeral Idesignates the gun body. This body may be composed of suitable metaland. if desired, may be made up of a number of sections, as illustratedin Figure l. which may be screwed together. The body is provided with aplurality of gun barrels 2 which may be screwed therein and behind eachbarrel is provided with a chamber 3 to receive a cartridge 4 which maybe fitted in said chamber before the corresponding barrel is screwedinto place. Each chamber 3 is somewhat smaller in transverse diameterthan the outside diameter of the corresponding barrel thus providing aninside, annular. outwardly facing shoulder 5.

Mounted in ,each barrel there is a bullet. or

pro ectile. 6 whose outer end is preferably pointed.

Figure 5 is a fragmentary, longitudinal, sec- The chambers and barrelsare usually regularly spaced along the gun and. in practice. they areregularly spaced around the gun usually about ninety degrees apart. Inthe present illustration. for convenience, they are all shown pointingin the same direction.

Between the inner end of each barrel 2 and the opposing shoulder 5 thereis inserted a supporting disc 1 preferably composed of metal. However,it may be made of any material that will withstand the hydrostaticressure of the well flu d; If the disc is composed of cond ctive m te il then it is ovi ed with a co uctor. suc s rivet. 8 which is insu a edfrom t e d sc b me ns of an insulating sleeve 9. said rivet andinsulating sleeve extending centrally through the disc I. Should thedisc I be composed of insulating material then the conductor 8 may beinserted directly through said disc without the necessity of insula- Thecartridge 4 inserted into the chamber 3 contains an explosive charge Inand a fuse wire ll extends from the conducting element 8 through theexplosive charge and is connected to the contact i2- which in turn is incontact with the gun body I.

when an. electric current is sent through the fuse wire the explosivecharge is ignited and explodes.

The bullet 6 is insulated from the barrel 2 by a suitable insulatingcoating butis in direct contact with the contact element, or rivet, 8.

The body I is provided with a bore l3 extending substantially from endto end of the body and leading from the muzzle end of each barrel aroundthe body there is a groove l4. A contact rod I! has its outer endextending into each groove l4 and its inner end projecting into the borel3, each contact rod being insulated from the body.

An electrical conductor I6 is connected, at one end, to each bullet andis located in the corresponding groove M with its other end connected tothe outer end of the corresponding contact rod l5.

Each insulating rod may be molded in a plug 1 of Bakelite'or similarinsulating material which may be threaded into the body I, as shown inFigure 3.

Within the bore l3 there is a sliding contact member which is designatedgenerally by the numeral l8 and which has two spaced flanges l9, l9formed of insulating material which fit rather snugly in said bore andbetween said flanges the sliding contact is provided with a wire brush20 of radial wires and thus forming a contact. The diameter of thiscontact 20 is somewhat less than that of the insulating flanges l9 sothat the wires will not contact the wall of the channel l3 but thisbrush is of sufiicient diameter so that the wires will touch each one ofthe contact rods l5 as the sliding contact l8 passes said contact rods.

Connected to the sliding contact l8 there is a conductor 2| which ispreferably insulated. This conductor 2| operates over an upper pulley 22mounted in the body and is coiled onto spool 23 which is mounted in thebody to turn on a vertical axis and is composed of insulating material.One flange of this spool carries a metallic ring 24 with which a brush25 is in constant frictional contact. This brush is electricallyconnected with a resistor'26 which in turn is connected to an insulatedrod 21 to which an insulated cable 28 is connected, which cable is usedfor suspending the gun perforator in the well and for carrying anelectrical current from a suitable source ofelectricity, as 29, at theground surface. One end of conductor 2| is connected to ring 24.

At the bottom of the body the conductor 2| passes over a pulley 30 andis wound on a spool 3| formed of insulating material and which ismounted to rotate on a. vertical axis. A coil igspring, as 32, isconnected to the 'spool 3| and tends to spool the conductor 2| onto thespool 3|.

There is an electric motor 33 in the body and associated with it thereis reduction gearing 34. A shaft 35 is driven from said motor throughsaid gearing. In the present illustration, the motor and gearing areshown diagrammatically. The shaft 35 is slidable axially through thespool 23 and carries a clutch 36 at its lower end by means of which theshaft may be clutched with and disengaged from said spool. shown onlydiagrammatically, as any conventional type of clutch may be used. Whenthe clutch is engaged with said spool 23, said spool will be driven fromsaid shaft, but when disengaged. the shaft will rotate independentlyfrom the spool.

There is a lever 31 beneath. the spool 23 and which is mounted to pivotby means of a transverse shaft 38. This lever is provided with twoadditional arms 39 and 40. Extended laterally through the wall of thebody |,'there is a shaft 4| whose inner end is provided with a cam 42and whose outer end is provided with a slotted This clutch is also head43. This shaft 4| is surrounded by a conventional stufling box-toexclude the well liquid.

It will be noted from an inspection of Figure 2 that the free end of thelever 3'! projects over the upper end of the bore I 3. It will also benoted that the cam 42 is positioned to co-act with the arm 40.Therefore, during the perforating operation, should the sliding contactl8 come into contact with said lever 31, upon further upward movement ofsaid sliding contact l8, the arm 39 will contact with and elevate anddeclutch the spool 23 from the shaft 35: also a turn of the shaft 4|will bring the cam 42 into contact with the arm 40, depressing said armand declutching the spool 23 from the shaft 35 as above stated.

At the lower end of the body, there is a bellows 44 which may be formedof any suitable material, either metal, rubber or plastic. This bellowsmay be provided with an externally threaded tubular nipple 45 whereby itmay be screwed into the body.

The upper end of the body is preferably formed with a detachable head 46which encloses the motor, gearing and the operative mechanism connectedtherewith. The motor is connected into the main electrical circuit whichis grounded on the body by the conductor 48.

With'the tool assembled as above described and as shown in Figure 2, itshould then be completely filled with an insulating fluid, such as oil.This fluid should fill the vacant space in the head 46, the bore I3 andthe bellows 44. Any change of volume of the insulating fluid, on accountof temperature or pressure variations, will be compensated by theexpansion or contraction of the bellows, thus keeping the pressurewithin the tool and on the outside of the tool the 'same.

When the tool is assembled and equipped with the firing units and filledwith the insulating fluid, the shaft 40 should be turned in order todisengage-the spool 23 from the clutch 36 so that the spool may freelyturn. Thereupon, the spring 32 on the lower spool 3| will wind theconductor l6 onto the spool 3|, thus moving the sliding contact l8 tothe lower end of the bore I3 and in position to make contact with thelower contact rod l5 as the sliding contact moves upwardly. The shaft 4|is then turned back to its neutral position and the gun perforator isthen lowered into the well. The main conductor 28 is grounded at thesurface and is provided with a switch 49 located so as to be readilycontrolled by an operator.

When the gun perforator has reached the selected position for firing,the switch 49 is closed. This will start the motor 1. However, anelectrical current will pass through the resistor 28, the brush 25,conductor 2|, contact rod l5, the conductor IS, the bullet 6, thecontact member 8, the fuse II and the contact |2 to the body and to theground.

The current passing through the fuse II will ignite the charge In andthe bullet 6 will be fired. With the switch 49 closed the motor 33 willcontinue the rotation of the shaft 35 and the spool 23 winding up theconductor 2|, and continue the movement of the sliding contact I8. Asthe contact moves between the spaced contacts l5the gun is inoperativebut, when the brush of the sliding contact comes into contact with thenext succeeding contact rod l5 above, the corresponding bullet 6 will befired and this procedure is repeated until all of the bullets are firedand the sliding contact 18 reaches the lever 3! and disen- 73 gages thespool 23 from the clutch 36. This will prevent the conductor 2| frombeing broken should the switch ddat the surface not be opened. a Fromthe'=foregoing it is evident that as many bullets may befired as desiredIf th'e body composed of a number of sectlons screwedyor otherwisesecured, together it is essential that the borel3 of the varioussections be perfectly aligned with the .bores of adiacent sectionssothat there will be a continuous smoothguide in which the slidingcontact l8 may move. 1 In this connection it is to be noted that theflanges i! of the sliding contact l8 should be slightlyfiexible so thatthey will readily pass theends otthe contact rods l5 which project intothe bore'l3i In the embodiment illustrated in Figure 5 there are twobores l3a which are oppositely arranged and which are connected attheirupper and lower ends.

"I'hese bores extend longitudinally through the body la. In thisembodiment the lower spool 3| is eliminated and there are two upperpulleys 22a,

22a and two lower pulleys 30a and 300. over which the conductor Ilapasses, said conductor being wound about the upper spool 23a and in thisembodiment being uninsulated. The spool 23a is provided with a band 24a,of copper or other conducting material, which is electrically connectedwith thering 24 and with which the conductor Zia is in constant contact.In other respects the embodiment illustrated in Figure 5 is the same asthat shown in Figure 2 except that the brush 20 is reversed by reversingthe direction of the motor II. In Figures 6 and '7 there is illustratedanother type of sliding contact wherein the body 50 is composed ofinsulating material and is preferably shaped to conform to the shape ofand to fit within the bore l3. In one side of this body there is alongitudinal groove 5| in which an outwardly bowed leaf spring 52 islocated with its ends suitably secured to said body 50. The spring 52 isconnected'to the core of the conductor 2|. The length of the body 50 isslightly greater than the distance between any two successive contactrods l5 so that the inner end of one of said rods is always engaged inthe groove with the result that this type of sliding contact ispermanently guided. As this sliding contact moves along the bore IS thespring 52 makes contact successively with the contact rods l5 and firesthe corresponding charges. Attached to the lower end of the body 50there is a wire, or cord, 53 which is wound on the spool 3| in the sameidentical manner, as is shown in Figure 2 and described in connectionwith said figure.

It may be here stated that another method of guiding the body 50 wouldbe to form the bore l3 polygonal in cross-section and correspondinglyshaping the body 50 so that it cannot turn relative to the contact l5.

As illustrated in Figure 2 the motor and reduction gearing together withthe spool 23 are located in the same housing, or head, 46. With anassembly of this type each gun perforator would have to be provided withits own motor and gear box. In some instances it may be desirable toassemble the motor and gear box in their own housing forming the head ofthe gun perforator, so that it may be easily attached to the body of thegun perforator itself by any selected type of coupling. This arrangementwould permit the use of the same head with various gun bodies so thatwhen it becomes necessary to repair or reload a body the head containingthe motor and gearing could be attached to another body.

The drawings and description are illustrative merely while the broadprinciple of the invention will be defined by the appended claims.

What I claim is:

1. In a gun perforator the combination of a gun body adapted to belowered into a well and having a longitudinal bore extendingsubstantially from end to end thereof, electrical circuits in the body,contact rods in, and insulated from, the body and extended into the boreand connected with the respective circuits, said rods being spaced alongthe bore substantially from end to end thereof, a sliding contact memberin the bore having means thereon which insulates it from the body andhaving electrical contact means thereon arranged to successively comeinto contact with said rods, 9. source of electrical energy connected tosaid contact means and to said circuits, means for moving said slidingcontact member along said bore.

2. In a gun perforator the combination of a gun body adapted to belowered into a well and having a longitudinal bore extendingsubstantially from end to end thereof, electrical circuits in the body,contact rods in, and insulated from, the body and extended into the boreand connected with the respective circuits, said rods being spaced alongthe bore substantially from end to end thereof a sliding contact memberin the bore having means thereon which insulates it from the body andhaving electrical contact meansthereon arranged to successively comeinto contact with said rods, a source of electrical energy connected tosaid contact means and to said circuits and electrically driven meansunder the control of an operator for moving the contact member alongsaid bore.

3. In a gun perforator the combination of a gun body adapted to belowered into a well and having a longitudinal bore which extendssubstantially throughout the length of the perforator, radial gunbarrels in the body and spaced apart substantially throughout the lengthof the perforator, projectiles in the barrels, explosive charges behindthe projectiles, electrical circuits in the body formed with filamentsassociated with said charges, contact rods insulated from the body andextended into the bore and connected with said respective circuits, acontact member movable in said bore and including guide means insulatingit from the bore walls and a contact arranged to electrically connectwith said rods, a source of electrical energy connected to said contactmember and to said electrical circuits, mechanical means for moving thecontact member to initial position and electrically driven means, underthe control of an operator, for moving said contact member along saidbore throughout the length thereof.

4. In a gun perforator the combination of a gun body adapted to belowered into a well and having a longitudinal bore, radial gun barrelsin the body, projectiles in the barrels, explosive charges behind theprojectiles. electrical circuits in the body formed with filamentsassociated with said charges, contact rods insulated from the body andextended into the bore and connected with said respective circuits, acontact member movable in said bore substantially throughout the lengthof the tool and including guide means insulating it from the bore wallsand a contact arranged to electrically connect with said rods, a sourceof electrical energy connected to said contact member and to saidelectrical circuits and electrically driven means under the control ofan operator for moving the contact member along gun body adapted to belowered into a well and having a longitudinal bore, electrical circuitsin the body, contact rods in, and insulated from, the body and extendedinto the bore and connected with the respective circuits, a slidingcontact member in the bore having means thereon which insulates it fromthe body and having electrical contact means thereon arranged tosuccessively come into contact with said rods, a source of electricalenergy connected to said contact means and to said circuits, mechanicalmeans for moving said contact member to initial position andelectrically driven means under the control of an operator for movingsaid contact member along the bore into successive contact with saidcontact rods.

4 6. In a gun perforator the combination of a gun body adapted to belowered into a well and having a longitudinal bore, electrical circuitsin the body, contact elements in, and insulated from, the body andextended into the bore and connected with the respective circuits, asliding contact member in the bore having means thereon which insulatedit from the body and having electrical contact means thereon arranged tosuccessively come into contact with said elements, a source ofelectrical energy connected to said contact means and to said circuits,mechanical means for moving said contact member to initial position andelectrically driven means under the control of an operator for movingsaid contact member along the bore into successive contact with saidcontact elements.

7. In a gun perforamr the combination or a gun body adapted to belowered into a well and having a longitudinal bore extendingsubstantially throughout the length of the tool, electrical circuits inthe body, contact elements in, and insulated from, the body and extendedinto the bore and connected with the respective circuits and arrangedalong the bore substantially from end to end thereof, a sliding contactmember in the bore having means thereon which insulates it from the bodyand having electrical contact means thereon arranged to successivelycome into contact with said elements, a source of electrical energyconnected to said contact means and to said circuits, means for movingsaid sliding contact member along said bore and means to main-' lain thecontact member against rotation in the PAUL CHARRIN.

REFERENCES CITED The following references are of record in the

